The radiochemistry core will continue to provide the radiopharmaceuticals, radiopharmaceutical quality control, metabolite analysis and regulatory documentation required by the projects to fulfill the goals of the research described in this application. The specific aims are to produce [11]C, [18]F, and [15]O, and to use these radionuclides to make the radiopharmaceuticals: 2-[[11]C]-thymidine; [[11]C]-verapamil; [[11]C]-doxorubicin; [[11]C]-carbon dioxide; [[18]F]-2-fluoro-2-deoxy-D-glucose; [[18]F]-fluoromisonidazole; [[18]F]-fluorothymidine; 16-alpha-[[18]F]-fluoroestradiol; and [[15]O]-water. The radiochemists are responsible for assuring the radiochemical purity and pharmaceutical quality of all products for in vivo studies and for compliance with all regulations regarding radiation and pharmaceutical safety.